Dedicated and partial path protection for survivability in heterogeneous optical networks

Abstract This paper addresses the issue of survivability in heterogeneous or mixed grid optical networks. In the design of a survivable network, resources are allocated to both primary and backup routes to ensure reliable connection establishment. In heterogeneous networks, both Routing and Wavelength Assignment (RWA) and Routing and Spectrum Assignment (RSA) are employed to establish connections traversing through fixed and flexible optical nodes. This work presents a mathematical model, associated constraints, and simulation results for connection recovery using Dedicated Path Protection (DPP) and Partial Path Protection (PPP). For PPP, three scenarios of backup spectrum recovery 75 %, 50 %, and 25 % are evaluated. The performance is assessed using metrics such as bandwidth blocking probability, network resource utilization, and Resource Overbuild Ratio (ROR). Simulation results indicate that the bandwidth blocking probability across different survivability strategies ranges from 5.65 % to 13.92 %, while network capacity utilization varies from 56.15 % to 69.39 % of the total network capacity.